HALFPIPE PLANS
Includes plans for a
4' Inline Skate Halfpipe,
3' Skateboard Halfpipe and a
Grinding Rail
www.rickdahlen.com
[email protected]
Materials List and Directions
4 x 8 x 3/4" Exterior Plywood (sanded one side)
4 x 8 x 3/8" Exterior Plywood (sanded one side)
2 x 4 x 8 Studs for skateboard version, 61 for the inline version
(18 of these should be pressure treated or sealed if you are choosing to put halfpipe on ground)
5-6 lbs 2" Galvanized Wood Deck Screws
5-6 lbs 3" Galvanized Wood Deck Screws
All measurements are exact, except where
I refer to 2x4. This is a standard name for
16
3" Lag Screws
studs that are actually 1 1/2 x 3 1/2.
16
11/4" Washers
16
1 - 11/4" Panhead Screws
2
11/2 ID PVC Pipe 8' (you can use metal pipe if you prefer)
7
8
59
1.
2.
3.
4.
5.
6.
3"
7.
8.
9.
10.
11.
12.
Measure and cut one curved end piece. Use this one to trace the other seven curved ends. (SEE PLAN A or B).
Mark out where the cross joists are positioned on the curved end pieces. Double check the position of the double
joist for the plywood decking seam. (SEE PLAN C).
Measure and cut cross joists for the four curved end structures. I used pressure treated 2x4's for the two bottom
cross joists that touch the ground.
Assemble the four curved structures. The plywood tends to bow a little after it is cut. Try to pick two pieces with
opposing bows for each of the curved sections. Start by attaching the cross joists at the top of the curved ends.
PREDRILLING THE HOLES IN THE PLYWOOD HELPS! Use two 3" screws at each end. DO NOT ATTACH
DECKING AT THIS TIME. (SEE PLAN D).
Assemble the frame for the bottom flat decking using 3" screws. I have provided two versions of the framework. One
if your halfpipe is going to be on a hard flat surface and one if it is going to be on a slightly uneven or soft ground.
DO NOT ATTACH DECKING AT THIS TIME. (SEE PLAN E or F).
Position your curved end structures and flat frame together where they will remain. (SEE PHOTO BELOW). Use
screws to fasten the pieces together. Screw the two curved ends together. Attach them to the flat framework, then
fasten it to the two curved structures on other end. DRILL VENT HOLES IN EACH OF THE ROWS (SEE PLAN E or F).
Using the 2" screws attach the two 4 x 8 x 3/4" sheets of plywood (smooth side up) to the flat framework. Screw
spacing should be approximately 6 - 8" apart. Note the plywood grain is going from side to side. I feel it provides
less chance of splinters. Predrilling was not necessary here.
Attach the coping on the corners of the curved ends with the panhead screws. (SEE PLAN G or H). I did it at this
time because I could stand in between the joists. I laid the PVC pipe on the ground and drilled my first eight holes
from the top straight through the bottom being careful to keep the drill at the same angle for all the holes. The first
drilling was just big enough for the screw to enter. I then redrilled just the top hole so I could get my screwdriver
through the hole. With the PVC pipe in position, using a MAGNETIC screwdriver, I inserted the screw through the
top hole down to the bottom hole in the wood. (SEE PLAN G or H).
Wet the back side (not the smooth side) of the 4 x 8 x 3/8" plywood. It will curl a little aiding in attaching it to the
curved ends. Put the bottom one on first with grain going from side to side. Attach the next bottom panel beside
it. You may premeasure and cut this panel before attaching it, or attach it and then trim it in position just below the
coping. Be careful you don't cut the coping though. Repeat the procedure for the next layer and the other side.
(SEE PLAN J). If you premeasure, note that the second layer top panel is slightly wider than the one below.
(SEE PLAN G or H). The curved decking is made of two layers of 3/8" plywood because it is bendable and you need
3/4" total thickness. I did not use as many screws on the bottom layer because I knew the top layer screws would
do the job for both layers.
Measure and attached the top platform decking using 2" screws.
Measure, cut and attach the vertical supports for the railing. I used a couple of clamps to hold them while I screwed
then in place. The horizontal supports were attached using two 3" wood screws at each cross over. After it was all
together I drilled holes and used the 3" lag screws and washers to anchor the railing. (SEE PLAN K).
You can paint it whenever you feel like it. This will give it added protection from the elements.
Frames put togther before
attaching the decking.
3'3"
4 - 4 x 8 sheets of 3/4" plywood
I think the best way to get all curves the
same is cut one and use it as a template
to draw the others.
For an eight foot wide halfpipe you will
need eight curved ends
A)
e(
d
s
Fis
7 1/2' radius
str
in
tch
l
ike
SKATE BOARD HALFPIPE TRANSITION CURVE (PLAN
Lin
hin
g
n't
s
oe
Thumb Tack
or nail
31/2"
g)
tre
4 - 4 x 8 sheets of 3/4" plywood
31/2"
I think the best way to get all curves the
same is cut one and use it as a template
to draw the others.
For an eight foot wide halfpipe you will need
eight curved sides.
B)
in
FI
sh
INLINE SKATE HALFPIPE TRANSITION CURVE (PLAN
e
gL
in
oe
(d
str
sn
't
5'
etc
h
lik
es
tr
7
1/
2"
r
a
diu
s
ing
)
You may have to adjust the
curve radius length to make
sure you don't overlap here.
1' 5 15/16"
Thumb Tack
or nail
1’
See Coping Detail (PLAN G)
SKATEBOARD CURVE SIDE
Space cross joists
approximately 8" apart
(PLAN C)
CHECK TO MAKE SURE
THIS DISTANCE IS 4FT.
It is important to put a double joist
here for the seam of the decking.
See Coping Detail (PLAN H)
It is important to put a double joist
here for the seam of the decking.
CHECK TO MAKE SURE
THIS DISTANCE IS 4FT.
CROSS JOIST
POSITIONING
1’
Space cross joists
approximately 8" apart
INLINE SKATE CURVE SIDE
D)
Attach each 2x4
with two 3" galvanized
wood screws (predrilling plywood helps)
See
Coping
Detail
Plan G
or H
You will need 4 of these structures
for your halfpipe
CURVED ENDS ASSEMBLY (PLAN
4x
2x
1
46
/2"
15 - 2x4 x 461/2"
1 - 2x4 x 461/2" ripped at angle
for coping edge (See
Coping Detail Plan G or H)
I used pressure
treated 2x4’s
were they touched
ground
NOTE: Double Joist for
plywood seam (See Cross
Joist Positioning Plan C)
All measurements are exact, except where I refer to 2x4. This
is a standard name for studs that are actually 1 1/2 x 3 1/2.
8' x 8' HALFPIPE BOTTOM PLATFORM FRAMEWORK (PLAN
E)
For unstable or slightly uneven ground
96" (8’)
45"
93"
93"
93"
vent holes
Attach curved end here
Attach curved end here
93"
1/2 -3/4"
Attach curved end here
Attach curved end here
45"
96" (8’)
2 - 2"x4" x 96" (8’)
Assemble the two 4’x8’ frames with two 3"
4 - 2"x4" x 93"
galvanized wood screws at each end,
24 - 2"x4" x 45" spaced approximately 8 3/8" apart
then screw the two frames together
2 - 4’x8’ x 3/4" plywood
to make an 8’x8’ frame.
DO NOT PUT PLYWOOD ON TOP
I made this frame work from pressure treated 2x4’s
UNTIL THE CURVED ENDS HAVE
and drilled vent holes in every row because I knew
BEEN ATTACHED.
it would not get much air circulation under decking.
All measurements are exact, except where I refer to 2x4. This
is a standard name for studs that are actually 1 1/2 x 3 1/2.
8' x 8' HALFPIPE BOTTOM PLATFORM FRAMEWORK (PLAN
F)
For flat solid ground
45"
vent holes
96"
96"
96"
96"
Attach curved end here
Attach curved end here
96"
Attach curved end here
Attach curved end here
1/2 -3/4"
45"
4 - 2"x4" x 96"
26 - 2"x4" x 45" spaced approximately 7 7/8" apart
2 - 4’x8’ x 3/4" plywood
I made this frame work from pressure treated 2x4’s
and drilled vent holes in every row because I knew
it would not get much air circulation under decking.
Assemble the two 4’x8’ frames with two 3"
galvanized wood screws at each end,
then screw the two frames together
to make an 8’x8’ frame
DO NOT PUT PLYWOOD ON TOP
UNTIL THE CURVED ENDS HAVE
BEEN ATTACHED.
All measurements are exact, except where I refer to 2x4. This
is a standard name for studs that are actually 1 1/2 x 3 1/2.
(SKATEBOARD HALFPIPE) COPING FRAMING DETAIL (PLAN G)
This detail is actual size. You can
use it to trace the notch for the coping.
2 - 11/2" ID Plastic PVC Pipe 8" long
16 - 1-11/2" Panhead Screws
Drill hole for size of screw
through both sides of PVC
pipe, Then enlarge top hole
for screwdriver.
Use a screwdriver with a
magnetized head.
Coping is approx. 1/2"
above decking here.
3/4"
Make sure coping
is a ittle higher
than decking here.
Plywood Platform
ipe
lfp
"P
Ha
)
gle
An
Evenly space 8 screws across 8' pipe.
All measurements are exact, except where I refer to 2x4. This
is a standard name for studs that are actually 1 1/2 x 3 1/2.
er
lay
r
d
ye
2n
t la
d
1s
oo
d
lyw
oo
"P
lyw
d
3 /8
ar
bo
te
ka
3 /8
(S
2x4
2x4 ripped
for angle of
curve.
(INLINE SKATE HALFPIPE) COPING FRAMING DETAIL (PLAN
H)
This detail is actual size. You can
use it to trace the notch for the coping.
Drill hole for size of screw
through both sides of PVC
pipe, Then enlarge top hole
for screwdriver.
Use a screwdriver with a
magnetized head.
2 - 11/2" ID Plastic PVC Pipe 8" long
16 - 1-11/2" Panhead Screws
Coping is approx. 1/2"
above decking here.
3/4"
Make sure coping
is flush or lower
than decking here.
Plywood Platform
line
(In
3 /8"
1st
All measurements are exact, except where I refer to 2x4. This
is a standard name for studs that are actually 1 1/2 x 3 1/2.
yer
er
lay
Evenly space 8 screws across 8’ pipe.
d la
2n
od
od
wo
Ply
)
gle
An
wo
pe
Ply
lfpi
Ha
3 /8"
ate
Sk
2x4
2x4 ripped
for angle of
curve.
CURVED DECKING (PLAN
J)
Material List is for both ends of halfpipe
1. 4- 4’x8’ x 3/8"
2. 4- ?x8’ x 3/8" (Cut width to fit)
WET BACK (UNFINISHED)
SIDE OF PLYWOOD
TO MAKE IT CURVE
3. 4- ?x4’ x 3/4"
(Cut width to fit)
2
1
Attach with 2"
galvanized wood screws
6"-8" spacing
2
1
3
4’
3
K)
Use 3" galvanized
wood screws
for assembly
at each crossover
6 - 2x4 x 8’
8 - 2x4 x 4’
16 - 11/4" Washers
16 - 3" Lag Screws
11/4" Washer
3" Lag Screw
Material List is for both railings of halfpipe
RAILING ASSEMBLY (PLAN
All measurements are exact, except where I refer to 2x4. This
is a standard name for studs that are actually 1 1/2 x 3 1/2.
1’
3’
GRINDING RAIL PLAN
11/2" ID Plastic PVC Pipe 10" long
4 x 6 x 10’ Wooden Beam
8 - 11/2" Panhead Screws
First cut the groove down the middle of the beam and bevel the edges.
There is not an exact angle for the cuts, just don’t make your groove cut too deep
so the screws don’t go into wood. I laid the PVC pipe on the ground and drilled
my first eight holes from the top straight through the bottom being careful to
keep the drill at the same angle for all the holes. The first drilling was just
big enough for the screw to enter. I then redrilled just the top hole so I
could get my screwdriver through the hole. With the PVC pipe in
position using a MAGNETIC screwdriver I inserted the screw
through the top hole down to the bottom hole into the wood.